Postgres FM

Nikolay Samokhvalov and Michael Christofides

A weekly podcast about all things PostgreSQL

  1. 9 HR AGO

    Gapless sequences

    Nik and Michael discuss the concept of gapless sequences — when you might want one, why sequences in Postgres can have gaps, and an idea or two if you do want them. And one quick clarification: changing the CACHE option in CREATE SEQUENCE can lead to even more gaps, the docs mention it explicitly. Here are some links to things they mentioned: CREATE SEQUENCE https://www.postgresql.org/docs/current/sql-createsequence.htmlSequence Manipulation Functions https://www.postgresql.org/docs/current/functions-sequence.htmlOne, Two, Skip a Few (post by Pete Hamilton from Incident io) https://incident.io/blog/one-two-skip-a-fewPostgres sequences can commit out-of-order (blog post by Anthony Accomazzo / Sequin) https://blog.sequinstream.com/postgres-sequences-can-commit-out-of-orderLogical Replication of sequences (hackers thread) https://www.postgresql.org/message-id/flat/CAA4eK1LC%2BKJiAkSrpE_NwvNdidw9F2os7GERUeSxSKv71gXysQ%40mail.gmail.comSynchronization of sequences to subscriber (patch entry in commitfest) https://commitfest.postgresql.org/patch/5111/Get or Create (episode with Haki Benita) https://postgres.fm/episodes/get-or-createGerman tank problem https://en.wikipedia.org/wiki/German_tank_problem ~~~ What did you like or not like? What should we discuss next time? Let us know via a YouTube comment, on social media, or by commenting on our Google doc! ~~~ Postgres FM is produced by: Michael Christofides, founder of pgMustardNikolay Samokhvalov, founder of Postgres.ai With credit to: Jessie Draws for the elephant artwork

    40 min

  2. 17 OCT

    LWLocks

    Nik and Michael discuss lightweight locks in Postgres — how they differ to (heavier) locks, some occasions they can be troublesome, and some resources for working out what to do if you hit issues. Here are some links to things they mentioned: Wait Events of Type LWLock https://www.postgresql.org/docs/current/monitoring-stats.html#WAIT-EVENT-LWLOCK-TABLEOur episode on (heavier) locks https://postgres.fm/episodes/locksNik’s new marathon posts https://postgres.ai/blog/tags/postgres-marathonPostgres LISTEN/NOTIFY does not scale (blog post by Recall ai) https://www.recall.ai/blog/postgres-listen-notify-does-not-scaleExplicit Locking https://www.postgresql.org/docs/current/explicit-locking.htmlpg_stat_activity https://www.postgresql.org/docs/current/monitoring-stats.html#MONITORING-PG-STAT-ACTIVITY-VIEWTuning with wait events for RDS for PostgreSQL https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/PostgreSQL.Tuning.htmlMultiXact member exhaustion incidents (blog post by Cosmo Wolfe / Metronome) https://metronome.com/blog/root-cause-analysis-postgresql-multixact-member-exhaustion-incidents-may-2025pg_index_pilot https://gitlab.com/postgres-ai/pg_index_pilotMyths and Truths about Synchronous Replication in PostgreSQL (talk by Alexander Kukushkin) https://www.youtube.com/watch?v=PFn9qRGzTMcPostgres Indexes, Partitioning and LWLock:LockManager Scalability (blog post by Jeremy Schneider) https://ardentperf.com /2024/03/03/postgres-indexes-partitioning-and-lwlocklockmanager-scalability ~~~ What did you like or not like? What should we discuss next time? Let us know via a YouTube comment, on social media, or by commenting on our Google doc! ~~~ Postgres FM is produced by: Michael Christofides, founder of pgMustardNikolay Samokhvalov, founder of Postgres.ai With credit to: Jessie Draws for the elephant artwork

    38 min

  3. 3 OCT

    User management

    Nik and Michael discuss user management in Postgres — how roles work, making administration easier, setting passwords, and avoiding them being logged. Here are some links to things they mentioned: Roles https://www.postgresql.org/docs/current/user-manag.html Privileges https://www.postgresql.org/docs/current/ddl-priv.htmlALTER DEFAULT PRIVILEGES https://www.postgresql.org/docs/current/sql-alterdefaultprivileges.htmlGRANT https://www.postgresql.org/docs/current/sql-grant.htmlREASSIGN OWNED https://www.postgresql.org/docs/current/sql-reassign-owned.htmlALTER ROLE (including SET) https://www.postgresql.org/docs/current/sql-alterrole.html CREATE ROLE https://www.postgresql.org/docs/current/sql-createrole.htmlHave I Been Pwned https://haveibeenpwned.comPwned Passwords API https://haveibeenpwned.com/API/v3#PwnedPasswordsCrunchy Data PostgreSQL Security Technical Implementation Guide (STIG) https://www.crunchydata.com/blog/announcing-the-crunchy-data-postgresql-stigOur episode on auditing https://postgres.fm/episodes/auditing ~~~ What did you like or not like? What should we discuss next time? Let us know via a YouTube comment, on social media, or by commenting on our Google doc! ~~~ Postgres FM is produced by: Michael Christofides, founder of pgMustardNikolay Samokhvalov, founder of Postgres.ai With credit to: Jessie Draws for the elephant artwork

    39 min

  4. 26 SEPT

    Postgres 18

    Nik and Michael discuss the newly released Postgres 18 — the bigger things it includes, some of their personal highlights, and some thoughts towards the future. Here are some links to things they mentioned: Postgres 18 announcement https://www.postgresql.org/about/news/postgresql-18-released-3142Postgres 18 release notes https://www.postgresql.org/docs/18/release-18.htmlSkip scan episode with Peter Geoghegan https://postgres.fm/episodes/skip-scanEasier Postgres fine-tuning with online_advisor https://neon.com/blog/easier-postgres-fine-tuning-with-online_advisorpganalyze Index Advisor https://pganalyze.com/index-advisorBUFFERS by default https://postgres.fm/episodes/buffers-by-defaultBuffers II (the sequel) https://postgres.fm/episodes/buffers-ii-the-sequelReturn of the BUFFERS https://postgres.fm/episodes/return-of-the-buffersUUID https://postgres.fm/episodes/uuidPartitioning by ULID https://postgres.fm/episodes/partitioning-by-uliduuidv7 and uuid_extract_timestamp functions https://www.postgresql.org/docs/current/functions-uuid.htmlAdd --no-policies option to pg_dump, pg_dumpall, and pg_restore https://git.postgresql.org/gitweb/?p=postgresql.git;a=commitdiff;h=cd3c45125Add ONLY support for VACUUM and ANALYZE https://git.postgresql.org/gitweb/?p=postgresql.git;a=commitdiff;h=62ddf7ee9Make "vacuumdb --analyze-only" process partitioned tables (committed recently for Postgres 19) https://commitfest.postgresql.org/patch/5871/NOT VALID constraints https://postgres.fm/episodes/not-valid-constraintsThe year of the Lock Manager’s Revenge (post by Jeremy Schneider) https://ardentperf.com/2024/03/03/postgres-indexes-partitioning-and-lwlocklockmanager-scalabilityIncrease the number of fast-path lock slots https://git.postgresql.org/gitweb/?p=postgresql.git;a=commitdiff;h=c4d5cb71d"enable" parameters will work differently in Postgres 18 https://www.pgmustard.com/blog/enable-parameters-work-differently-in-postgres-18logerrors https://github.com/munakoiso/logerrors ~~~ What did you like or not like? What should we discuss next time? Let us know via a YouTube comment, on social media, or by commenting on our Google doc! ~~~ Postgres FM is produced by: Michael Christofides, founder of pgMustardNikolay Samokhvalov, founder of Postgres.ai With credit to: Jessie Draws for the elephant artwork

    56 min

  5. 19 SEPT

    Gadget's use of Postgres

    Nik and Michael are joined by Harry Brundage from Gadget to talk about their recent zero-downtime major version upgrade, how they use Postgres more generally, their dream database, and some challenges of providing Postgres as an abstracted service at scale. Here are some links to things they mentioned: Harry Brundage https://postgres.fm/people/harry-brundageGadget https://gadget.devZero downtime Postgres upgrades using logical replication (blog post) https://gadget.dev/blog/zero-downtime-postgres-upgrades-using-logical-replicationHOT updates https://www.postgresql.org/docs/current/storage-hot.htmlPgDog https://pgdog.devMultigres https://multigres.comNeki https://www.neki.devRunning 10 Million PostgreSQL Indexes In Production (Heap blog post) https://www.heap.io/blog/running-10-million-postgresql-indexes-in-productionpgwatch2 (Postgres.ai Edition) https://gitlab.com/postgres-ai/pgwatch2Advanced query insights on AlloyDB https://cloud.google.com/alloydb/docs/advanced-query-insights-overviewOrioleDB https://www.orioledb.comNot discussed but relevant: Gadget have also now published a blog post about their sharding! https://gadget.dev/blog/sharding-our-core-postgres-database-without-any-downtime ~~~ What did you like or not like? What should we discuss next time? Let us know via a YouTube comment, on social media, or by commenting on our Google doc! ~~~ Postgres FM is produced by: Michael Christofides, founder of pgMustardNikolay Samokhvalov, founder of Postgres.ai With credit to: Jessie Draws for the elephant artwork

    53 min

  6. 12 SEPT

    turbopuffer

    Nik and Michael are joined by Simon Eskildsen from turbopuffer — among other things, they discuss ANN index types, tradeoffs that can make sense for search workloads, and when it can make sense to move search out of Postgres. Here are some links to things they mentioned: Simon Eskildsen https://postgres.fm/people/simon-eskildsenturbopuffer https://turbopuffer.comUse ULID Idempotency Keys (tip 6 in this blog post from Shopify) https://shopify.engineering/building-resilient-payment-systemsPostgreSQL 18 Release Candidate 1 https://www.postgresql.org/about/news/postgresql-18-rc-1-released-3130Understanding DiskANN (blog post by Junaid Ahmed) https://www.tigerdata.com/blog/understanding-diskannSPFresh: Incremental In-Place Update for Billion-Scale Vector Search (paper) https://arxiv.org/abs/2410.14452Amazon S3 adds new functionality for conditional writes https://aws.amazon.com/about-aws/whats-new/2024/11/amazon-s3-functionality-conditional-writesAmazon S3 Vectors https://aws.amazon.com/s3/features/vectors ~~~ What did you like or not like? What should we discuss next time? Let us know via a YouTube comment, on social media, or by commenting on our Google doc! ~~~ Postgres FM is produced by: Michael Christofides, founder of pgMustardNikolay Samokhvalov, founder of Postgres.ai With credit to: Jessie Draws for the elephant artwork

    50 min

  7. 5 SEPT

    When not to use Postgres

    Nik and Michael discuss when not to use Postgres — specifically use cases where it still makes sense to store data in another system. Here are some links to things they mentioned: Just use Postgres (blog post by Ethan McCue) https://mccue.dev/pages/8-16-24-just-use-postgresJust Use Postgres for Everything (blog post by Stephan Schmidt) https://www.amazingcto.com/postgres-for-everythingReal-time analytics episode https://postgres.fm/episodes/real-time-analyticsCrunchy Data Joins Snowflake https://www.crunchydata.com/blog/crunchy-data-joins-snowflakeTwo sizes fit most: PostgreSQL and Clickhouse (blog post by Sid Sijbrandij) https://about.gitlab.com/blog/two-sizes-fit-most-postgresql-and-clickhousepg_duckdb episode https://postgres.fm/episodes/pg_duckdbCloudberry https://github.com/apache/cloudberryTime-series considerations episode https://postgres.fm/episodes/time-series-considerationsQueues in Postgres episode https://postgres.fm/episodes/queues-in-postgresLarge Objects https://www.postgresql.org/docs/current/largeobjects.html PGlite https://pglite.devParadeDB https://www.paradedb.comZomboDB https://github.com/zombodb/zombodbturbopuffer https://turbopuffer.comHNSW vs. DiskANN (blog post by Haziqa Sajid) https://www.tigerdata.com/learn/hnsw-vs-diskannSPANN: Highly-efficient Billion-scale Approximate Nearest Neighbor Search (paper) https://www.microsoft.com/en-us/research/wp-content/uploads/2021/11/SPANN_finalversion1.pdfAmazon S3 Vectors https://aws.amazon.com/s3/features/vectorsIterative Index Scans added to pgvector in 0.8.0 https://github.com/pgvector/pgvector/issues/678S3 FDW from Supabase https://github.com/supabase/wrappers/tree/main/wrappers/src/fdw/s3_fdw ~~~ What did you like or not like? What should we discuss next time? Let us know via a YouTube comment, on social media, or by commenting on our Google doc! ~~~ Postgres FM is produced by: Michael Christofides, founder of pgMustardNikolay Samokhvalov, founder of Postgres.ai With credit to: Jessie Draws for the elephant artwork

    46 min

  8. 29 AUG

    Disks

    Nik and Michael discuss disks in relation to Postgres — why they matter, how saturation can happen, some modern nuances, and how to prepare to avoid issues. Here are some links to things they mentioned: Nik’s tweet demonstrating a NOTIFY hot spot https://x.com/samokhvalov/status/1959468091035009245Postgres LISTEN/NOTIFY does not scale (blog post by Recall ai) https://www.recall.ai/blog/postgres-listen-notify-does-not-scaletrack_io_timing https://www.postgresql.org/docs/current/runtime-config-statistics.html#GUC-TRACK-IO-TIMINGpg_test_timing https://www.postgresql.org/docs/current/pgtesttiming.html PlanetScale for Postgres https://planetscale.com/blog/planetscale-for-postgresOut of disk episode https://postgres.fm/episodes/out-of-disk100TB episode https://postgres.fm/episodes/to-100tb-and-beyond Latency Numbers Every Programmer Should Know https://gist.github.com/jboner/2841832Fio https://github.com/axboe/fio ~~~ What did you like or not like? What should we discuss next time? Let us know via a YouTube comment, on social media, or by commenting on our Google doc! ~~~ Postgres FM is produced by: Michael Christofides, founder of pgMustardNikolay Samokhvalov, founder of Postgres.ai With credit to: Jessie Draws for the elephant artwork

    46 min
See All (163)

About

A weekly podcast about all things PostgreSQL

Information

  • Creator
    Nikolay Samokhvalov and Michael Christofides
  • Years Active
    2022 - 2025
  • Episodes
    163
  • Rating
    Clean
  • Copyright
    © 2025 Nikolay Samokhvalov and Michael Christofides

You Might Also Like